Continuous strip slot insulation



Dec. 7, 1948.

R. o. GOLDBERG CONTINUOUS STRIP SLOT INSULATION Filed Feb. 7, 1947 i 1 I x v a re 2 W fi m e w w W i 5 m m w o Patented Dec. 7, 1948 CONTINUOUS STRIP SLOT. INSULATION Richard 0. Goldberg, Chicago, 111:, assignor to Pioneer Gen-E-Motor Corporation,

Chicago,

111., a corporation. of Delaware.

Application February 7, 1947, ScrialNo. 727,096

My invention relates to improvement in continuous strip slot insulators and has for one object to provide anew and improved type of insulation which may be used to insulate the windings of an electrical rotor.

Another object of the invention is to provide in a single strip, which may be easily and conveniently assembled With the rotor, the insulating means lining the slots between the rotor poles.

Other objects of the invention will appear from time to time in the specification.

My invention is illustrated more or less diagrammatically in the accompanying drawings wherein:

Figure 1 is a side elevation of the rotor;

Figure 2 is a section view along the line 2-2 of Figure 1;

Figure 3 is a section view on a large scale along the line 3-3 of Figure 1;

Figure 4 is a plan view of the insulating strip in its extended position;

Figure 5 is a side elevation of the strip as assembled ready I or installation; and

Figure 6 is a section view along the line 66 of Figure 3.

The invention is illustrated in the drawings as applied to a suitable type of electric rotor, but it will be understood that the application is merely illustrative, and the insulating strip might be used with many different types of rotors.

I is a rotor shaft the details of which form no part of the invention. 2 is an insulating sleeve on the rotor shaft. 3 is the rotor mounted on the shaft I and having between it and the shaft the insulating sleeve 2. The rotor comprises an annular portion A. Projecting therefrom are a plurality of angularly spaced pole pieces 5, each pole piece being laterally extended at the outer periphery of the rotor as indicated at 6. Located at each end of the rotor is an insulating member 1 which has projecting therefrom radial fingers 8' conforming generally to the pole pieces ibut terminating just short of. the lateral extensions 6. Thus. each end. of each pole piece and, eachiend of the: angular portion 5' is provided with an in.- sulating member.

In the past it has been customary to insert into the angular space between each. pair of pole pieces an insulating strip which is. held in ,place by the lateral extension 6 which is V-shaped and extends fromend to end of the rotor. Such pieces are small and difiicult to handle, and. difiicult. to assemble and store.

As a substitute for suchseparate insulating pieces I provide a single integral insulatlngstrip 14 Claims. (Cl. 171-206) 9. That strip is scored or marked for bending along the central axis I'll, ID, and alternate sides ofth'e: strip are notched as. at II, I2, the notches extending inwardly'in each case only as far as the. center line I6, Ill. The distance between, the notch II on one side and'the next notch I2 on the other side of the strip is substantially equal to the axial length of the rotor pole pieces 5.

The flat continuous strip indicated in Figure 4 maybe bent along the axial line [0 and then each double section bent back upon itself at the notches II and I2 toproduce the structure shown in Figure 5, where the curved members I3 are in alignment with the notches II and I2.

In assembling, one of thebent-back portions I4 will be inserted into the angular space between a pair of pole pieces; 5. The natural elasticity of the; paper will cause it to spring out as indicated at I5 beneath the overhanging member 6. The next double back section IE will then be bent around the curved portion I3 as indicated, enclosing. one of the radial strips 8-, and this bentback portion will be pressed into the next angular opening I1. This process continues until a V- shaped section of. the insulating strip has been placed in each angular space between the pole pieces 5.

Under these circumstances there will be one of:the curved portions I3 at one end of each polepieee. The otherend of each pole: piece will be insulated by one of the radial members associated- With the insulating member 8. Thus the entire body of the radial pole piece will beinsulated, and the natural spring. of the paper will .hold the insulation in place with the outer longitudinal edges maskedby the overhanging members .6 on the pole pieces 5.. Then, when electric wire is wound about each pole piece, it will. be effectively insulated-from the rotor by the strip and the star-shaped end insulating discs, and the overhang of the member 8.- co-operating with the outwardspringing of the insulating sheet will insurethat thewindings will be placed within the insulating member and not between it andthe rotor.

As. indicated,, the notches II and I2 have sub stantial; width. Their width measured in a direction parallel with the axis I0, I0 is of little consequence. They may be wide or narrow, depending upon the width in a tangential direction oftherotor pole pieces. Under some circumstances these notches may even take the form only of a slit in the paper.

I claim:

1. Insula ting means for electric rotors and, the

like, comprising a thin, fiat longitudinally extended strip of flexible insulating material, longitudinally scored along its central axis, the strip being notched on opposed sides thereof at a plurality of spaced points along both sides, the notches alternating and extending inwardly substantially to the scored center line the opposite walls of the notches being parallel and perpendicular to the scored center line.

2. An insulating means for electric rotors comprising a plurality of flexible insulating strips, each strip being bent to V-shape along the longitudinal axis thereof, each strip being joined to an adjacent strip by a curved integral section substantially the width of one-half the strip.

3. In combination a rotor having a plurality of radial pole pieces angularly spaced one from another, an integral continuous insulating strip extending through the angular spaces between each pair of pole pieces, the part of the strip associated with each pair of pole pieces being integrally joined with the part of the strip associated with an adjacent pair of pole pieces a part of the strip masking one end of each of the pole pieces, the entire body of the strip being inside the outer periphery of the pole pieces.

4. An insulator for electric rotors comprising a plurality of flexible, thin insulating strips, each strip being bent to V-shape along its longitudinal axis and each strip being joined to an adjacent similarly bent strip by a section substantially half the width of the strip, said joining sections being alternately disposed on opposite sides of the strip.

5. In combination a rotor, including a plurality of radially disposed, angularly spaced pole pieces, lateral extensions projecting tangentially from the outer end of each pole piece, a continuous insulating strip located within the space defined by each pair of adjacent pole pieces, engaging the opposed walls of said pole pieces and masked by the laterally extended pole piece portions, the strip in each angular space being joined to the strip in the adjacent angular space by an integral portion whose width is substantially the same as the width of that portion of the strip engaging one wall of one pole piece.

6. In combination with a rotor having angularly spaced pole pieces, a single insulating strip whose width is approximately twice the radial extent of each pole piece, there being alternate notches on opposite sides of the strip, normal to the axial line of the strip, equalling in depth substantially half the width of the strip, the distance between a notch on one side of the strip and the adjacent notch on the other side being substantially equal to the axial length of the pole piece.

'7. An insulator for electric rotors and the like, comprising a plurality of elongated insulating strips, each strip being folded about the longitudinal central axis thereof into a V-shape, each strip being attached to an adjacent strip by an integral piece Whose width is one-half the width of the strip.

8. In combination with an electric rotor having a plurality of radially disposed elongated pole pieces, an insulator comprising a plurality of insulating strips, each substantially equal in length to the axial length of the pole pieces, each strip being folded about its longitudinal central axis into a V-shape adapted to lie in the angle between two adjacent pole pieces, each strip being connected to an adjacent strip lying in an adjacent angle between adjacent pole piecesby an 4 integral portion whose width is one-half the width of the strip.

9. An insulator for electric rotors and the like, comprising a plurality of elongated insulating strips, each strip being folded about the longitudinal central axis thereof into a V-shape, each strip being attached to an adjacent strip by an integral piece whose width is one-half the width of the strip, each integral joining piece being associated only with the adjacent branches of two adjacent V-shapes.

10. In combination with an electric rotor having a plurality of radially disposed elongated pole pieces, an insulator comprising a plurality of insulating strips, each substantially equal in length to the axial length of the pole pieces, each strip being folded about its longitudinal central axis into a V-shape adapted to lie in the angle between two adjacent pole pieces, each strip being connected to an adjacent strip lying in an adjacent angle between adjacent pole pieces by an integral portion whose width is one-half the width of the strip, each integral joining piece being associated only with the adjacent branches of two adjacent V-shapes,

11. An insulator for electric rotors and the like, comprising a plurality of elongated insulating strips, each strip being folded about the longitudinal central axis thereof into a V-shape, each strip being attached to an adjacent strip by an integral piece whose width is one-half the width of the strip, one of the joining strips joining one branch of the V at one end with a similar branch in an adjacent V-shaped section, the other strip joining the opposed branch of the first-mentioned V with the V-shaped strip at the other end of the first-mentioned V.

12. In combination with an electric rotor having a plurality of radially disposed elongated pole pieces, an insulator comprising a plurality of insulating strips, each substantially equal in length to the axial length of the pole pieces, each strip being folded about its longitudinal central axis into a V-shape adapted to lie in the angle between two adjacent pole pieces, each strip being connected to an adjacent strip lying in an adjacent angle between adjacent pole pieces by an integral portion whose width is one-half the width of the strip, one of the joining strips joining one branch of the V at one end with a similar branch in an adjacent V-shaped section, the other strip joining the opposed branch of the first-mentioned V with the V-shaped strip at the other end of the first-mentioned V.

13. Insulating means for electric rotors and the like, comprising a thin, fiat longitudinally extended strip of flexible insulating material, longitudinally scored along its central axis, the strip being notched on opposed sides thereof, at a plurality of spaced points along both sides, the notches alternating and extending inwardly substantially to the scored center line, the opposite walls of the notches being parallel and perpendicular to the scored center line, each notch being bounded at its bottom by curved line generally tangent to the scored center line, the width of each notch being greater than the thickness of the strip of material.

14. In combination a rotor having a plurality of radial pole pieces angularly spaced one from another, an integral continuous insulatin strip extending through the angular spaces between each pair of pole pieces, the part of the strip associated with each pair of pole pieces being in tegrally joined with the part of the strip associated with an adjacent pair of pole pieces, a

portion of the insulating strip masking one end of one pole piece and the opposite end of each The following references are of record in the file of this patent:

UNT'IED STATES PATENTS adjacent pole piece. Number Name t RICHARD O. GOLDBERG. 43,3 0 Remus June 8, 1886 5 1,913,333 Eaton June 6, 1933 REFERENCES CITED 2,303,777 Warshaw Dec. 1, 1942 2,311,857 Noah et a1. Feb. 23, 1943 

